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1.
Scarlett Lin Gomez Cynthia D O'Malley Antoinette Stroup Sarah J Shema William A Satariano 《BMC cancer》2007,7(1):193
Background
Colorectal cancer, if detected early, has greater than 90% 5-year survival. However, survival has been shown to vary across racial/ethnic groups in the United States, despite the availability of early detection methods. 相似文献2.
3.
E L Engelhardt M Sankar C Y Wu-Wang M R Thomas W R Walker J Neu 《Journal of pediatric gastroenterology and nutrition》1991,12(4):494-500
Using the neonatal piglet, the effects of dietary cholesterol deprivation on growth, intestinal enzyme activity, intestinal and hepatic 3-hydroxy-3-methylglutaryl-coenzyme A reductase (HMG-CoA reductase), and serum lipid were studied. Six litters of piglets were randomly assigned to one of two feeding regimens: restricted (800 ml of formula/24 h) versus unrestricted (1,200 ml of formula/24 h). Within litters, piglets were separated by sex, then randomly assigned to a formula containing low cholesterol (less than 2 mg/dl) or high cholesterol (145 mg/dl). Piglets were fed for 2 weeks. Male piglets in the restricted low cholesterol group gained significantly less weight per milliliter of formula than the restricted high cholesterol males. No effect was observed in the females. Microvillus membrane lactase activity was greater in males fed a high versus low cholesterol diet. Intestinal and hepatic HMG-CoA reductase activities and serum lipid profiles showed a trend toward compensation for dietary cholesterol deprivation but did not differ statistically between the cholesterol-fed versus -deprived groups. It is concluded that dietary cholesterol deprivation in the male neonatal pig causes alterations in growth, but no other statistically significant responses were detectable in this study. 相似文献
4.
5.
We report on an 22-month-old white girl with tetraploidy who is growing well, but who is extremely delayed in psychomotor development. When counseling parents it is important to realize that, although quite rare, tetraploid individuals can be born alive and live for at least 22 months. The implications are also relevant to prenatal diagnosis. 相似文献
6.
Antoinette MaassenVanDenBrink MSc ; Monique N. Vergouwe MSc ; Roel A. Ophoff PhD ; Pramod R. Saxena MD PhD ; Michel D. Ferrari MD PhD ; Rune R. Frants PhD 《Headache》1998,38(4):288-291
The 5-HT1 receptor agonist, sumatriptan, is highly effective in the treatment of migraine. Some patients, however, do not respond or experience recurrence of the headache. In addition, some patients report chest symptoms after sumatriptan. We investigated whether these different responses could be attributed to genetic diversity of the 5-HT1B receptor, which most likely mediates the therapeutic action and the coronary side effects of sumatriptan. Allele frequencies of two polymorphisms in the 5-HT1B receptor gene ( G861C and T-261G ) were investigated in migraine patients with consistently good response to sumatriptan (n=14), with no response (n=12), with recurrence of the headache (n=12), with chest symptoms (n=13), and in patients without chest symptoms (n=27). Allele frequencies (G:0.74; C:0.26 at nt 861 and T:0.39; G:0.61 at nt -261) did not differ between patient groups, indicating that genetic diversity of the 5-HT1B receptor does not seem to be involved in the different clinical responses to sumatriptan. 相似文献
7.
O. Kempski F. Staub F. V. Rosen M. Zimmer A. Neu A. Baethmann 《Molecular and chemical neuropathology / sponsored by the International Society for Neurochemistry and the World Federation of Neurology and research groups on neurochemistry and cerebrospinal fluid》1988,9(1-3):109-125
The pathophysiological chain of events occurring during cerebral ischemia is still poorly understood on a molecular level. Therefore, an in vitro model to study glial swelling mechanisms, using C6 glial cells under controlled extracellular conditions, has been established. Flow cytometry serves to determine even small cell volume changes. In this report, the effects of anoxia and acidosis on glial swelling are summarized. Anoxia alone, or in combination with iodoacetate to inhibit anaerobic glycolysis, did not cause an increase of glial volume for up to 2 h. Acidification of the incubation medium below pH 6.8, on the other hand, was immediately followed by cell swelling to 115% of normal. Amiloride or the absence of bicarbonate and Na+ in the medium significantly reduced glial swelling. The data support the contention that swelling results from an activation of the Na+/H+-antiporter to control intracellular pH. It is suggested that swelling in an ischemic penumbra is promoted by this mechanism. Therapeutic approaches to control cerebral pH might be useful to protect brain tissue in cerebral ischemia. 相似文献
8.
Inclusion of satellites in an 18/21 translocation chromosome shown by ammonical-silver staining (sat-banding) in case of partial trisomy 18.
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R L Neu C C Ortega G A Barg W Pinto Jr L I Gardner W M Howell T E Denton 《Journal of medical genetics》1976,13(6):520-522
A male infant with a partial trisomy 18 and a 46,XY, --21, t(18;21)(18qter replaced by 18q12::21 p13 replaced by 21 qter) chromosome complement is described. The translocation chromosome is of special interest because it includes the satellites of chromosome 21. This was shown by differential satellite staining with the ammoniacal-silver technique. 相似文献
9.
Mersch PP Vastenburg NC Meesters Y Bouhuys AL Beersma DG van den Hoofdakker RH den Boer JA 《Journal of affective disorders》2004,80(2-3):209-219
Background: The Seasonal Pattern Assessment Questionnaire (SPAQ) is a frequently used screening instrument in the research on Seasonal Affective Disorder (SAD). Nevertheless, studies on its reliability and validity are relatively scarce. In the present study the reliability and the contrast validity of the SPAQ are investigated. Methods: SAD patients, selected by means of a clinical interview, non-seasonal depressed out-patients, non-depressed out-patients, and a control group, are contrasted to estimate the discriminating power of the SPAQ. Also, the reliability and factor structure of the seasonality and the climate subscales are investigated. To study food intake the Seasonal Food Preference Questionnaire (SFPQ) was developed. Results: The SAD criterion of the SPAQ shows good specificity (94%), but a low sensitivity (44%). Discriminant analysis shows sufficient ability to classify subjects (81% correctly classified). The Global Seasonality Scale has a good internal consistency. It consists of two factors, a psychological factor and a food factor. The SFPQ is sensitive for carbohydrate intake by SAD patients. Limitations: Most SAD patients had received treatment and completed the SPAQ while they were not depressed, which may have influenced the sensitivity. Conclusions: The SPAQ is not sensitive enough to be considered a diagnostic instrument for SAD. Nevertheless, it is accurate enough to be used as a screenings instrument. The only false positives were found in the depressive group. The accuracy of prevalence Figs. can be improved by completion of the SPAQ in the summer months, combined with the completion of a depression scale. 相似文献
10.
N. X. Chin J. W. Gu H. C. Neu 《European journal of clinical microbiology & infectious diseases》1990,9(9):685-691
The activity of the new oral cephalosporin Bay v 3522 was compared to that of six other beta-lactam agents. Bay v 3522 inhibited methicillin-susceptibleStaphylococcus aureus andStaphylococcus epidermidis at 2 µg/ml, compared to MICs of 8 µg/ml for the other cephalosporins tested. It was more active againstStreptococcus pyogenes (MIC 0.06 µg/ml) than cefuroxime, cefixime, cephalexin and cefaclor. Groups B, C and G streptococci were inhibited at 0.12 µg/ml, while the MIC90 forStreptococcus bovis and viridans streptococci was 0.5 and 2 µg/ml, respectively. The MIC90 for enterococci andListeria monocytogenes was 8 µg/ml.Clostridium perfringens was inhibited by 0.12 µg/ml, but mostBacteroides spp. were resistant. The MIC90 for beta-lactamase positiveEscherichia coli (producing primarily TEM-1) was >64 µg/ml and for beta-lactamase negative strains 16 µg/ml. The MIC90 for high-level beta-lactamase producingKlebsiella pneumoniae was >64 µg/ml versus 4 µg/ml for other isolates. The MIC90 forMoraxella catarrhalis was 2 µg/ml, forHaemophilus influenzae 1 µg/ml, and forNeisseria gonorrhoeae 4 µg/ml.Enterobacter cloacae, Citrobacter freundii, Proteus mirabilis, Providencia spp. andPseudomonas aeruginosa were resistant. Bay v 3522 was destroyed by TEM-1, SHV-1, TEM-3 and P99 beta-lactamases. 相似文献